Do we all go "PFFFFT"?

[Animal Mother]

When removing the fuel cap, are we supposed to get a "PFFFT" sound (gas/air escaping under pressure) or is there supposed to be no pressure. I know on some cars this can be a bad thing.

[Cullam3n]

How much petrol do you usually have left before you open your fuel cap?

Apparently the psssht is more pronounced the closer to empty you are.

However on my 80 I don't get that noise at all but my mate's 20v does.

[Animal Mother]

How much petrol do you usually have left before you open your fuel cap?

Apparently the psssht is more pronounced the closer to empty you are.

However on my 80 I don't get that noise at all but my mate's 20v does.

Does it regardless of the amount of fuel. I know my Rangie never used to do it but was a problem if it did, hence my concern.

[4WheelDrifter]

I had this problem on my old Coupé. It could be a breather problem. Best remove the carbon canister to be on the safe side. Well, it worked for me.

Make sure your N80 is working for a start, it might be worth temporarily venting the expansion tank to the atmosphere to isolate the problem. I'm not familiar with the UrS4/6 setup, but there is a float valve and a check valve between the tank and the carbon canister on the 3B.

[Animal Mother]

Make sure your N80 is working for a start, it might be worth temporarily venting the expansion tank to the atmosphere to isolate the problem. I'm not familiar with the UrS4/6 setup, but there is a float valve and a check valve between the tank and the carbon canister on the 3B.

I know there must be a carbon canister somewhere but I haven't a clue where.

What is the N80?

[s2_bo]

I used to get a noise too but only when filling up from near empty. - after removing the CC like 4wheeldrifter suggested above it no longer makes a noise.

[s2driveruk]

hmmm i get this on the coupe.....and now getting a petrol fume smell from the engine bay. no obvious leaks but could the two be linked to the carbon canister then?

[s2_bo]

Could also be your breather system thats creating the smell. I used to get a smell of fumes at WOT when my catch tank was not venting properly.

Are you running the stock system or a catch tank of some sort?

[s2driveruk]

bog standard Bo...

[LHD_Kid]

Damn.... this has got me worried now, never really thought about it.... mine also does it, andis louder the emptier the tank gets..... should it not do it at all then???
We NEED a definitive answer on this one....
Chris

[Nuvo]

I thought this was normal. The natural gassing of the fuel produces some build up of pressure in the tank. More significantly, unwanted fuel is passed through the pressure regulator back to the tank. It is the restriction in the fuel line created by the pressure regulator that provides the system with its operating pressure.